Odd bump-offset behaviour when enabling Virtual Textures

[ca_user]

Hi all!

I was doing some material-work and got started on adding in bump-offset to add some extra detail.
When I did though, the material completely broke (as can be seen in the screenshot below).
After a few tests I have narrowed it down to virtual texturing interfering with the bump-offset.
Or rather, the fact that the same texture is sampled twice is interfering with it.

Swapping out the first sample of the brick texture (which has height in the alpha channel)
with a separate height texture does not show the issue.

So the question is, is there a way around this double-sampling issue without turning off virtual-textures?

The issue:

The material:

[BananableOffense]

You might try changing some settings in the sampler nodes, or the texture asset. But if no settings can circumvent it, it seems the only solution would be to separate the height map into a different texture.

[ca_user]

After some fiddling around with the settings it appears I am unable to fix the issue without separating out the height-map. So likely that’ll have to be the fix. Thank you for your help!